Transcript Optical Satellite Communication ECE

PRESENTATION
ON
OPTICAL SATELLITE
COMMUNICATION
Presented by:
DHARAMVEER
Roll No. 48120802
Introduction:
Communication links between space
crafts is an important element of space
infrastructure, particularly where such
links allow a major reduction in the
number of earth stations needed to
service the system.
SEVERAL TYPES OF SATELLITE

LEO

MEO

GEO
GEO
Originally proposed by Author C.
Clarke
Circular orbit above the equator.
Angular separation about 2
degree allows 180 satellites.
Round trip time to satellite about
0.24 sec.
EARLY SATELLITES
 Relay - 4000 miles orbit
 Telstar
 Allowed Line transmission across
the Atlantic.
 Syncom 2 - First Geosyndronous
satellite.
LINK DESIGN OF SATELLITE
 Wavelength and Polarization
 Link Budgets for an asymmetric link
 Pointing
 Acquisition
 Tracking
DIRECT DETECTION OPTICAL
TERMINAL
OVERVIEW OF THE SOUT
TERMINAL
The SOUT terminal consists of two main
parts: a terminal head unit and a remote
electronics module (REM). The REM contains the
digital processing electronics for the pointing
acquisition and tracking (PAT) and terminal
control
functions
together
communications electronics.
with
the
OPTICAL ANTENNA
The optical antenna comprises the telescope and
coarse
pointing
assembly.
The
CPA uses
stepping motors together with a conventional
spur gear and planetary gear. The total height of
the optical antenna is a major contributor to the
height of the CPA above the platform which
affects LEO and GEO link.
OPTICAL ANTENNA
MAJOR PROBLEMS FOR
SATELLITES
 Positioning in Orbit
 Stability
 Power
 Communication
 Harsh Environment
THANK YOU